The present invention relates to composite structures of glass fabric and thermoplastic resin. More specifically, it is directed to such structures wherein the glass fabirc is knitted, the resin is a perhalopolyfluoroethylene polymer resin in sheet form and the fabric is partially embedded in one surface of the fabric.
U.S. Pat. No. 3,446,686 discloses laminating sheets of plastic to fabric for reinforcement purposes, followed by forming a shaped article from the resultant laminate. The patent discloses that the disadvantage of this method is that the fabric has a limited degree of elongation and thus tends to rupture during the forming step. The patent further discloses overcoming this disadvantage by laminating the fabric to the plastic during the forming step. This is accomplished by placing a sheet of thermoplastic material over the adhesive coated surface of knitted glass fabric, heating the sheet of thermoplastic material and drawing the sheet and fabric into the mold to form the shaped article. Upon cooling, the adhesive adheres the fabric to the molded sheet of thermoplastic material. This approach has the disadvantage of the adhesive being the weak link in the composite structure.